Air-brake mechanism for railway-cars



2 Sheets-Sheet 1.

(Np Model.)

(1. W. HIGGINS; AIR BRAKE MECHANISM FOR, RAILWAY ems.-

Patented Aug. 8, 1893'.

v No. 503,088.

....... 7 1 a Q I It Hi 1 R Q 7% l \7 x t x W ,v

, u M & W

2' Sheets-8.1166112.

Patented Aug. 8",

H I IIII 0. W. HIGGINS. AIR BRAKE MEQHANISM FOB; RAILWAY CARS.

(Np Model.)

UNITED STATES PATENT OFFICE.

CHARLES W. HIGGINS, OF FERNWOOD, ILLINOIS, ASSIGNOR, BY DIRECT AND MESNEASSIGNMENTS, OF TI-IREE-FOURTHS .TO JACOB B. KNUDSON AND HAROLD E.KNUDSON, OF SAME PLACE, AND LEONARD C. B. HOLMBOE,

OF CHICAGO, ILLINOIS.

AIR-BRAKE MECHANISM FOR RAILWAY-CARS.

SPECIFICATION forming part of Letters Patent No.-503,083, dated August8, 1893.

Application filed April 18, 1890.

To all whom it may concern.-

Be it known that I, CHARLES W. HIGGINS, residing at Fernwood, in thecounty of Cook and State of Illinois, have invented certain new anduseful Improvements in Air-Brake Mechanism for Railway-Cars, of which Ido declare the following to be a full, clear, and exact description,reference being had to the accompanying drawings, forming part of thisspecification.

My present invention has relation more particularly to what is known asthe triple valve mechanism of air-brake apparatus, this triple valvemechanism servingto connect the brakepipe to the auxiliary reservoir,and serving also to connect this reservoir with the brakecylinder. Thetriplevalve mechanism is arranged as well-understood in the art, so thatby the variation of the air-pressure within the train-pipe, the valvemechanism will be shifted in such manner as to admit air from theauxiliary reservoir to the brake-cylinder to apply the brakes, and atthe same time out 01f communication between the brake-pipe and theauxiliary reservoir, and in such manner also as to restore the supply ofair from the brake-pipe to the auxiliary reservoir, and at such time,permit the escape of air from the brake-cylinder to release the brakes.

The object of my present invention is to improve the construction oftriple valve mechanism, and this object I have accomplished by the novelfeatures of construction and combination of parts hereinafter described,illustrated in the accompanying drawings, and particularly pointed outin the claims at the end of this specification.

Figure 1 is a view in vertical longitudinal section-through an auxiliaryreservoir, and brake cylinder, of ordinary construction, and through atriple valve mechanism, of my improved construction attached thereto.Figs. 2, 3 and 4 are enlarged views in vertical longitudinal sectionthrough my improved valve 5 mechanism, these several views showing theparts in difierent positions. Fig. 5 is a view in vertical transversesection on line 55 of Fig. 2. Fig. 6 is a detail fraction view invertical section on line 6-6 of Fig. 3. Fig. 7 is ner.

Serial No. 348,442. (No model.)

a detached face view of the cap wherein the graduating spring andemergency valve are contained. Fig.8 is a view in vertical section online 88 of Fig. 1.

A designates the auxiliary reservoir and A denotes the brake cylinderconveniently attached thereto in any of the usual ways, as for exampleby means of the cylinder pipe at, that leads through the auxiliaryreservoir A, and connects with .the cylinder port or chan nel 2 in thebody of the triple valve. The cyl- 6o inder port or channel 2 leads fromend to end of the body of the triple valve,and communicates with achannel 3 in the body of the cap or casing C, this channel 3communicating with the train-pipe channel 4, to which the train-pipewill be connected in the usual man- Within the piston valve chamber Bofthe triple valve body is located the piston D of the triple valve, thestem (1 of this piston having fixed thereto or formed in piecetherewith, the slide valve D. The portion of the body B of the triplevalve wherein the stem 01 and slide valve D are held is provided withgrooves 10 and 11 to form guide ways in which the edges of the slidevalve D will move, and is formed also with lateral spaces 12 to permitthe flow of air past the slide valve, from the piston valve chamber B ofthe triple valve easing into the auxiliary reservoir. The slide valve Dis provided preferably with a spring 8o 13 set within a suitable recess14, of the slide valve, and serving to prevent the accidental slippingof the valve while allowing it to be freely moved.

The cap or casing C is formed separate from the'piston valve chamber Bof the triple valve body, and is connected thereto by suitable bolts 15passing through flanges of the valve-body and of the cap or casing. Thecap 0 is by preference formed as a hollow casting 0 having a face plate0 wherein are formed the air ports 0 and 0 one on each side of thechannel or passage 3, and on the back of this face plate is formed achamber 0 to receive the graduating spring E. One end of this'95graduating spring sets within the chamber 0 while its opposite endencircles a projection f extending backwardly from the louder F that iscarried by the arm F. This arm F may be formed in piece with or affixedto the buffer F, but by preference the arm is of spring metal attachedas at 18 to the cap or casing G and arranged to move freely within thecut-away space 19 formed in the extension 0 at the back of the faceplate 0 of the cap or casing G.

Upon the inner face of the pistonvalv chamber B of the triple valve bodyis formed a small feed groove or passage 1) extending a short distancebackward, and leading down the front face B of the piston valve chamberto the space formed within the portion B of the valve body, (as shownmore particularly in Fig. 6 of the drawings.) In the wall of the slidevalve chamber B is formed one or more escape ports 20, leading to theouter air, and from these escape ports is extended also the escape port21 leading to the slide valve chamber formed within the valve body.Through the valve body also is formed the supply passage or channel 30that leads from the interior of the slide valve chamber B to thecylinder-port or channel 2. The slide valve D is provided with a mainsupply port or channel d which leads from the end of the slide valvenext the auxiliary reservoir to the side of the valve adjacent thesupply passage or channel 30; and adapted to be brought coincidenttherewith as will presently more fully appear. By preference also theslide valve D is provided with a relief port or channel (1 leading fromthe end of the slide valve opposite the auxiliary reservoir through theedge of the valve adjacent the passage or channel 30 and adapted to bebrought coincident therewith. In the edge of the slide valve D is alsoformed the exhaust cavity d this exhaust cavity being of sufficientlength to span the distance between the escape passage 21 and the supplypassage or channel 30, in order to release the pressure of air withinthe brake cylinder as will presently more fully appear.

The operation of so much of my improved,

e as follows: When the tripple valve mechanism is in its normal positionthat is to say when the brakes are out of action, the parts will be inthe relative position shown in Fig. 1 of the drawings. At this time, thepiston D by which the slide valve Dwill be controlled, will be at theextreme end of its piston valve chamber B, and the slide valve D willoccupy such position that the exhaust cavity 61 will connect the supplypassage or channel 30 with the escape port or channel 21, therebypermitting the air within the brake-cylinder to escape and consequentlypermitting the brakes to be drawn from off the wheels of the car. Atsuch time, however, the pressure of air within the auxiliary reservoir Awill be equal to the pressure of air within the train pipe, and thechanneht leading thereto, since at such time, the supply of air from theair-pump of the locomotive, will pass through the channel 4 into the capor casing 0, through the port 0 and c of the plate 0, into the pistonvalve chamber B, and by way of the small feed passage binto the spacearound the stem 61 of the piston D, and thence through the passages 12into the auxiliary reservoir A. If now, however, it is desired to applythe brakes gradually in order to decrease the speed of the train orslowly stop it, the engineer will operate the engineers valve in theusual manner so as to slightly decrease the pressure of air within thetrain pipe, and consequently within the passage or channel 4communicating therewith, and within the piston valve chamber B behindthe piston D. As soon as this decrease of pressure within the train pipeoccurs, the excess pressure within the auxiliary reservoir will forcethe piston D backward, as seen in Fig. 2 of the drawings, until theparts assume the position seen in Fig. 3 of the drawings, at which timethe passage or channel d of the slide valve D Will come coincident withthe supply passage or channel 30 that leads to the brake cylinder supplypipe 2, and consequently the air supply within the auxiliary reservoir Awill pass through the channels 30 and 2, into the pipe a, and thenceinto the brake cylinder A, causing a movement of the piston A of thisbrake cylinder sufiicient to gradually apply the brakes of the car.During its backward movement, the piston D will contact with the bufferF moving backward this buffer against the force of its spring arm F andthe graduating spring E. By this backward movement of the slide valve D,it is plain that the escape port 21 will be closed. As soon, however, asthe pressure in the auxiliary reservoir has been reduced by expansioninto the brake-cylinder, to such extent that this pressure becomes equalto that within the train pipe, the graduating springE and the spring armF will force forward the butter F and the piston D until a blank part ofthe slide valve D passes over and closes the supply port or channel 30,thereby retaining within the brake cylinder its pressure, and applyingthe brakes with a force exactly proportionate to the reduction ofpressure made in the train pipe by the engineer. If now the brakes areto be released in order to permit the train to go ahead or back, theengineer by the operation of the engineers valve, will increase thepressure within the train pipe 4,

thereby causing the piston D to move back to the position seen in Fig.1, and causing the excess of air to pass through the small feed grooveor channel I) of the piston valve chamber B into and through the slidevalve chamber B of the triple valve to the auxiliary reservoir, and atthe same time the slide valve D will be moved forward until its exhaustcavity d connects the supply channel 30 with the escape port or channel21, and thereby permits the release of the air supply from the brakecylinder A by way of the pipe a, the

channel 2, the passage or channel 30, the cavity d and the escape port21.

In order to effect a sudden stopping of the train, I have provided anemergency valve G, this valve being located within the cap or casing atthe mouth of the channel or passage 3. The emergency valve G is carriedby a stem g, the rear portion of this stem extending through aperforation formed for the purpose in the plate 0, and the forwardportion of the stem extending into a perforation it formed in the screwplug H held within a correspondingly threaded perforation in the cap orcasing 0. Upon the rear portion of this stem g is placed a coiled springg, a portion of this spring being held within a suitable seat formed inthe screw-plug H. This spring g serves to normally hold the emergencyvalve G against its seat, and prevent the direct passage of air from thetrain pipe and the passage i into the channel or passage 3. It will beobserved that the forward end g of the emergency valve extends intoproximity to the back portion or extension of the piston D, so that whenthe piston is moved a sufficient distance, it will contact with the endof the stem 9 and lift the emergency valve G from its seat. Hence itwill be seen that if the engineer desires to suddenly stop the train, itwill be only necessary to so decrease the pressure of air in the trainpipe that the excess pressure within the auxiliary reservoir shall forcethe piston D backward until it not only contacts against and movesbackward the buffer B, but also as seen in Fig. 4, strikes the stem 9 ofthe emergency valve G, thereby forcing backward and unseating thisvalve, and permitting the direct pressure of air to pass from the brakepipe and the channel it into and through the channels or passages 3, and2, and the pipe at to the brake cylinder, and permitting also thepassage of air from the auxiliary reservoir by the passage or channel din the slide valve D into and through the channel 30 to the passage 2,and thence to the brake cylinder pipe at and the brake cylinder.Manifestly therefore when the emergency valve is unseated, the desiredpressure within the brake cylinder will be effected, not merely by thepassage of air from the auxiliary reservoir, but as'well also by thestraight air supply from the train pipe through the channels 4, 3, 2,and the brake cylinder pipe a.

In order to throw 0d the brakes after the sudden stopping of the trainhas been effected in manner last described, it is only necessary for theengineer to increase the pressure of the air supply within the trainpipe, thereby causing the piston D to be forced inward to the positionseen in Fig. 1 of the drawings. As the piston is thus forced inward theemergency valve G will return to its seat, the piston D will uncover thesmall feed groove 1) permitting the passage of air into the auxiliaryreservoir and the slide Valve D will be moved inward until its exhaustcavity 01 connects the passage or channel 30 with the escape port orchannel 21 thereby permitting the release of the air pressure within thebrake cylinder through the pipe at, channel 2, passage or channel 30,exhaust cavity 01 and escape port or channel 21, so that the brakes willbe thrown from off the wheels. In order to prevent the passage of airfrom the auxiliary reservoir back into the train pipe, when the supplywithin the train pipe has been diminished, to set the brakes, I preferto place within the channel or passage 2 a back pressure valve K,opening inward only, as shown by dotted lines. Hence it will be seenthat when either the passage 01' or cl of.the slide valve 1) is broughtcoincident with the passage 30 that leads to the passage or channel 2,and the brake cylinder pipe at, the supply of air from the auxiliaryreservoir will pass to the brake cylinder, and will be prevented by theback pressure valve K from passing into the channel 3 and unseating theemergency valve.

By providing the slide valve D with the port 01', as shown and byconnecting this valve so that it shall move in unison with the piston D,the necessity is avoided for the use of any supplemental valve withinthe slide valve, and the construction is rendered much more simple andeffective than in prior devices of this character with which ,I amfamiliar. So also, the provision of a supplemental channel d in theslide valve D insures a more ready passage of the air from the auxiliaryreservoir to the brake-cylinder, when a sudden stopping of the train isdesired. By the use of a spring arm F for sustaining the bufier F, theforce of the graduating spring E can be augmented as desired, and a morecertain shifting of the piston D and the slide valve D at the desiredtime can thereby be effected. The employment of a cap or casing 0 forsustaining the emergency valve and for forming the channels 3 and 4 alsogreatly simplifies the construction and is a material improvement notmerely in that it enables the parts to be readily reached for cleaningand repairs, but because it enables a more direct supply of air from thetrain pipe through the passages or channels 4, 3, and 2 to the brakecylinder pipe at, and consequently insures a quicker action upon thepiston of the brake cylinder when the brakes are to be suddenly applied.

The precise details of construction above set out maybe varied by theskilled mechanic without departure from the spirit of the invention, andto such precise details therefore I do-not wish the invention to beunderstood as restricted, nor do I wish the reference letters ashereinafter used in the claims to be understood as restricting theinvention to the precise construction, location and arrangement of theparts designated by said refererence letters as such letters are used toavoid confusion and not for the purpose of limitation.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. The combination of a triple valve body having a suitable slide valvechamber and a suitable piston valve chamber, and having an air supplypassage or channel leading from said slide valve chamber to a passage orchannel connecting with the brake cylinder, a slide valve within saidslide valve chamber provided with a passage or channel communicatingwith the auxiliary reservoir, and adapted to be brought coincident withthe air-supply channel that connects with the brake cylinder, a suitablepiston within the piston valve chamber, a perforated cap for said valvebody, having channels or passages for connecting the train-pipe with thechannel or passage of the valve body that leads to the brake-cylinder,an emergency valve located within said cap, and having a stem extendinginto position to be struck by the piston in its backward movement, and agraduating spring adapted to move said piston after said emergency valvehas been restored toits seat, and by which the shifting of the slidevalve can be effected to close the passage between the auxiliaryreservoir and the channel that leads to the brake-cylinder,substantially as described.

2. The combination of a triple valve body having a slide valve chamberand a piston valve chamber and having an air supply passage leading fromsaid slide valve chamber to a passage or channel connected with thebrake cylinder, a slide valve within said slide valve chamber providedwith a passage or channel communicating with the auxiliary reservoir andadapted to be brought coincident with the air supply channel thatconnects with the auxiliary reservoir, a piston within the piston valvechamber, to which piston the slide valve is fixed so that the valveshall partake of the entire movement of the piston, a graduating springand a butter with which said piston will contact, and apassage orchannel connecting the triple valve body with the train pipe,substantially as described.

3. In triple valve mechanism, the combination with a suitable valvebody, havinga piston valve chamber, and a suitable slide valve chamber,and a suitable piston and slide valve located within said chambers, of aperforated cap for said valve body, said cap being provided withpassages or channels for the flow of air from the train pipe to apassage or channel that leads to the brake cylinder, an emergency valvefor obstructing the flow of air through the passages of said cap, aspring for holding said emergency valve to its seat, and a graduatingspring independent of the emergency valve, and adapted to effect themovement of the piston and slide valve, without any shift of theemergency valve, substantially as described.

4. In triple valve mechanism, the combination, with a valve body havinga slide valve chamber and a piston valve chamber and suitable ports andpassages, and a slide valve.

and a piston within their respective chambers, and acap for said body ofan emergency valve arranged to be struck by the piston about the extremeof its movement, and a graduating spring arranged to operateindependently of the emergency valve and adapted to elfect the movementof the slide valve in ordinary operation without unseating the emergencyvalve, substantially as described.

CHARLES W. HIGGINS.

Witnesses:

GEo. P. FISHER, J r., J A003 13. KNUDSEN.

